Prolonged exposure to elevated temperature leads to severe thermal stress in the broad-nosed pipefish, Syngnathus typhle

ABSTRACT

Changes in water temperature may have profound effects on physiology, metabolism, and fish behaviour. However, much of the existing research is based on relatively short-term experiments. In the context of climate change, where water temperatures are increasing seasonally, and the frequency and duration of extreme heatwave events are rising, incorporating longer exposure periods will provide a better understanding of the potential effects of warming on marine species. Here, we tested the effects of prolonged exposure to elevated temperature on broad-nosed pipefish, Syngnathus typhle. Fish were exposed to ambient (20ºC) and high (24ºC) temperatures for a four-month period, during which activity levels, growth and survival were monitored. Fish under high temperature were less active when compared to fish under ambient temperature, grew less, and survival was dramatically decreased. These findings have significant implications for the long-term sustainability of broad-nosed pipefish populations, as the species may struggle to adapt to future ocean conditions.

KEYWORDS:

• Activity
• behaviour
• climate change
• survival
• Syngnathidae

Acknowledgments

The authors would like to thank António Roleira for the valuable assistance throughout the experimental work; André Lima for collecting temperature data in Ria Formosa Lagoon; and volunteers from ISPA fish facilities for their valuable help with daily routines at the lab.

Disclosure statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Data availability statement

The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.

Ethics statement

This study was carried out under the approval of Direção-Geral de Alimentação e Veterinária (DGAV, Portuguese Authority for Animal Health, permit 0421/000/000/2020) and according to the University’s animal ethics guidelines.

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/10236244.2024.2378752.

Additional information

Funding

This study had the support of FCT through UIDB/MAR/04292/2020, UIDP/MAR/04292/2020 awarded to MARE, and through the project [LA/P/0069/2020] granted to the Associate Laboratory ARNET. The study also benefited from a PADI Foundation grant attributed to AF.